1. Field of the Invention
This invention is particularly related to the production of collars and the like which are particularly used in heating and ventilating systems. In such systems, heated or cooled air is introduced into ducts, and pipes are connected to the ducts at various positions for directing the air to individual rooms or areas. To accomplish this, holes are formed in duct walls, and connectors including rectangular or circular collars are attached at these holes. Pipe sections are then attached to the connectors.
2. Description of the Prior Art
In a typical connector design, an edge of the connector is provided with a plurality of spaced apart notches. The hole in the duct wall is dimensioned to receive this edge, and the tabs which are formed between the notches are then bent outwardly whereby the connector can be secured relative to the duct wall. The opposite side of the connector may be crimped for purposes of facilitating the attachment of a pipe section to the connector.
Equipment for producing connectors of the type described is readily available. Thus, notched edges can be formed in various ways, and crimping rollers are also well known constructions. The notching and crimping steps are thus independently conducted, and the order of the steps is not critical.